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Sandra Brown March 7, 2012 Page 3 discharge pipe designed and installed to alleviate the potential pressure head on the mountain above the Bear Mine. MCC obtained approval from the Colorado Department of Public Health and Environment (CDPHE) for the Lone Pine Gulch pipeline discharge point ( Outfall 013) to discharge mine water from the NW Panels sealed sump to Lone Pine Gulch. Amendment No. 2 to MCC's existing Colorado Discharge Permit System (CDPS) Permit Number CO- 0038776 allowed for the new outfall for discharge of up to 0.072 MGD to Lone Pine Gulch, a tributary to the North Fork of the Gunnison River. The quality of water within the sump was evaluated and found to be of sufficient quality so as not to require additional treatment in a pond prior to discharge to Lone Pine Gulch. Because the water quality was believed to be similar to that from existing mine water outfall 011 due to its source, all effluent limitations and monitoring frequencies were made the same for both outfalls. Amendment No. 3 effective May 1, 1997 and expiring April 30, 2000 allowed MCC to increase outfall 013 effluent flow to 2,000 gpm or a maximum of 2.88 MGD. The discharge pipe installed in Lone Pine Gulch was completed in August 1997 and discharged mine water typically less than 500 gpm to the Lone Pine Gulch and ultimately to the North Fork of the Gunnison River for a little more than two years beginning in early January 1998. The pipeline was reclaimed and dismantled in approximately 2002. Landslide Activity and Development of the Seep The permit area of the Bear No. 3 Mine is located on the south side of the North Fork of the Gunnison River in an area characterized by steep mountainous slopes that are potentially unstable. The Division has studied this area extensively. As described in a 1998 memo from Dr. Jim Pendleton formerly of our Division, the mine permit area has been characterized by frequent and extensive mass wasting events since 1983. The Bear Mine portals and portal fan were damaged by mudflow events on several occasions. Rotational landslides have damaged the portal access road and portal bench on several occasions. The valley slope above the mine site evidences several large ancient scarps and an extensive mudflow complex. Two significant landslides occurred at the site in 1996 and 1997. Numerous large, open scarps and tension fractures above the landslide that occurred in 1997 have been identified and mapped by Wright Water Engineers (WWE). On March 30 and 31 of 1996, a landslide occurred above the Bear Mine access road which extended vertically to the North Fork of the Gunnison River. The slide also extended horizontally from the ventilation fan on the west into the ephemeral drainage east of the mine access road. This massive slide destroyed the portal access drainage system and the slope drainage monitoring system which included upper and lower French drains. In an investigation by J.E. Stover & Associates, the cause of the slide could be attributed to water from either snow melt and spring precipitation or other sources of groundwater that were not identified. On November 17, 1997 the Division was notified of a slide located immediately west of the reclaimed Bear No. 3 Mine portals. The slide became active on a Saturday, November 15 Debris from the slide flowed onto the old coal stockpile pad (west of the reclaimed stacking tube) and into the North Fork of the Gunnison River south of the mine access bridge. Shortly after the slide occurred, water started flowing from the east side of the slide scarp. One warm (approx. 85° F.) spring has flowed continually since November 17, 1997, two days after the